The letters, publicized by the Council on American-Islamic Relations (CAIR), tell Muslims to “pack your bags and get out of dodge,” and promise a “cleanse” coming to America in the wake of Trump’s election. Trump campaigned on pledges to monitor activity in mosques, create a Muslim registry temporarily bar Muslims from entering the U.S.

“You Muslims are a vile and filthy people,” a letter posted by CAIR says. “But your day of reckoning has arrived. There’s a new sheriff in town—President-elect Donald Trump.”

“He’s going to cleanse America and make it shine again. And he’s going to start with you Muslims,” the letter continues. It was signed, simply, “Americans for a Better Way.”

CAIR said copies of the letter were mailed to three mosques and California and one in Georgia. Leaders from the organization have called on Islamic institutions across the country to bulk up security in response to hundreds of reports of anti-Muslim activity. According to the FBI, anti-Muslim incidents increased by 67% in 2015. CAIR’s Georgia branch plans to host an interfaith open house in January.

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